The number of marks for each question is indicated in brackets 1. [12] Evaluate the limit, if it exists. a) x + 3x lim 13x-x- 12 (2 + h) - 8 lim vx+9 - 5 lim x+4 d) 3.x2 + 4x + 1 lim 1--1 x+1 3. [5] Explain why the function is discontinuous at the given number a. Sketch the graph of the function. X if x * 1 f(x) = r - 1 a =1 if x = 1 4. [6] Find the numbers at which f is discontinuous. At which f these numbers is f continuous from the right, from the left, r neither? Sketch the graph of f. +l ifxsi f(x) - 3-x if | 4